#ifdef _WIN32
#include "getopt.h"

#ifdef __cplusplus
extern "C" {
#endif

#ifdef REPLACE_GETOPT
int opterr = 1; /* if error message should be printed */
int optind = 1; /* index into parent argv vector */
int optopt = '?'; /* character checked for validity */
#undef optreset /* see getopt.h */
#define optreset __mingw_optreset
int optreset; /* reset getopt */
char* optarg; /* argument associated with option */
#endif

static void _vwarnx(const char* fmt, va_list ap)
{
    (void)fprintf(stderr, "%s: ", __progname);
    if (fmt != NULL)
        (void)vfprintf(stderr, fmt, ap);
    (void)fprintf(stderr, "\n");
}

static void warnx(const char* fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);
    _vwarnx(fmt, ap);
    va_end(ap);
}

/*
    Compute the greatest common divisor of a and b.
*/
static int gcd(int a, int b)
{
    int c;
    c = a % b;
    while (c != 0)
    {
        a = b;
        b = c;
        c = a % b;
    }
    return (b);
}

/*
    Exchange the block from nonopt_start to nonopt_end with the block
    from nonopt_end to opt_end (keeping the same order of arguments
    in each block).
*/
static void permute_args(int panonopt_start, int panonopt_end, int opt_end,char* const* nargv)
{
    int cstart, cyclelen, i, j, ncycle, nnonopts, nopts, pos;
    char* swap;
    /*
        compute lengths of blocks and number and size of cycles
    */
    nnonopts = panonopt_end - panonopt_start;
    nopts = opt_end - panonopt_end;
    ncycle = gcd(nnonopts, nopts);
    cyclelen = (opt_end - panonopt_start) / ncycle;
    for (i = 0; i < ncycle; i++)
    {
        cstart = panonopt_end + i;
        pos = cstart;
        for (j = 0; j < cyclelen; j++)
        {
            if (pos >= panonopt_end)
                pos -= nnonopts;
            else
                pos += nopts;
            swap = nargv[pos];
            /* LINTED const cast */
            ((char**)nargv)[pos] = nargv[cstart];
            /* LINTED const cast */
            ((char**)nargv)[cstart] = swap;
        }
    }
}

#ifdef REPLACE_GETOPT
/*
    getopt --
    Parse argc/argv argument vector.

    [eventually this will replace the BSD getopt]
*/
int getopt(int nargc, char* const* nargv, const char* options)
{
    /*
        We don't pass FLAG_PERMUTE to getopt_internal() since
        the BSD getopt(3) (unlike GNU) has never done this.

        Furthermore, since many privileged programs call getopt()
        before dropping privileges it makes sense to keep things
        as simple (and bug-free) as possible.
    */
    return (getopt_internal(nargc, nargv, options, NULL, NULL, 0));
}
#endif /* REPLACE_GETOPT */

//extern int getopt(int nargc, char * const *nargv, const char *options);

#ifdef __cplusplus
}
#endif
/*
    POSIX requires the `getopt' API to be specified in `unistd.h';
    thus, `unistd.h' includes this header.  However, we do not want
    to expose the `getopt_long' or `getopt_long_only' APIs, when
    included in this manner.  Thus, close the standard __GETOPT_H__
    declarations block, and open an additional __GETOPT_LONG_H__
    specific block, only when *not* __UNISTD_H_SOURCED__, in which
    to declare the extended API.
*/

#ifdef __cplusplus
extern "C" {
#endif

struct option /* specification for a long form option...    */
{
    const char* name; /* option name, without leading hyphens */
    int has_arg; /* does it take an argument?     */
    int* flag; /* where to save its status, or NULL   */
    int val; /* its associated status value       */
};

enum /* permitted values for its `has_arg' field... */
{
    no_argument = 0, /* option never takes an argument    */
    required_argument, /* option always requires an argument  */
    optional_argument /* option may take an argument      */
};

/*
    parse_long_options --
    Parse long options in argc/argv argument vector.
    Returns -1 if short_too is set and the option does not match long_options.
*/
static int parse_long_options(char* const* nargv, const char* options,const struct option* long_options, int* idx, int short_too)
{
    char* current_argv, *has_equal;
    size_t current_argv_len;
    int i, ambiguous, match;
#define IDENTICAL_INTERPRETATION(_x, _y) \
    (long_options[(_x)].has_arg == long_options[(_y)].has_arg && long_options[(_x)].flag == long_options[(_y)].flag && long_options[(_x)].val == long_options[(_y)].val)
    current_argv = place;
    match = -1;
    ambiguous = 0;
    optind++;
    if ((has_equal = strchr(current_argv, '=')) != NULL)
    {
        /* argument found (--option=arg) */
        current_argv_len = has_equal - current_argv;
        has_equal++;
    }
    else
        current_argv_len = strlen(current_argv);
    for (i = 0; long_options[i].name; i++)
    {
        /* find matching long option */
        if (strncmp(current_argv, long_options[i].name,
                    current_argv_len))
            continue;
        if (strlen(long_options[i].name) == current_argv_len)
        {
            /* exact match */
            match = i;
            ambiguous = 0;
            break;
        }
        /*
               If this is a known short option, don't allow
               a partial match of a single character.
        */
        if (short_too && current_argv_len == 1)
            continue;
        if (match == -1) /* partial match */
            match = i;
        else if (!IDENTICAL_INTERPRETATION(i, match))
            ambiguous = 1;
    }
    if (ambiguous)
    {
        /* ambiguous abbreviation */
        if (PRINT_ERROR)
            warnx(ambig, (int)current_argv_len,
                  current_argv);
        optopt = 0;
        return (BADCH);
    }
    if (match != -1)   /* option found */
    {
        if (long_options[match].has_arg == no_argument
                && has_equal)
        {
            if (PRINT_ERROR)
                warnx(noarg, (int)current_argv_len,
                      current_argv);
            /*
                 XXX: GNU sets optopt to val regardless of flag
            */
            if (long_options[match].flag == NULL)
                optopt = long_options[match].val;
            else
                optopt = 0;
            return (BADARG);
        }
        if (long_options[match].has_arg == required_argument || long_options[match].has_arg == optional_argument)
        {
            if (has_equal)
                optarg = has_equal;
            else if (long_options[match].has_arg == required_argument)
            {
                /*
                           optional argument doesn't use next nargv
                */
                optarg = nargv[optind++];
            }
        }
        if ((long_options[match].has_arg == required_argument)
                && (optarg == NULL))
        {
            /*
                 Missing argument; leading ':' indicates no error
                 should be generated.
            */
            if (PRINT_ERROR)
                warnx(recargstring,
                      current_argv);
            /*
                 XXX: GNU sets optopt to val regardless of flag
            */
            if (long_options[match].flag == NULL)
                optopt = long_options[match].val;
            else
                optopt = 0;
            --optind;
            return (BADARG);
        }
    }
    else     /* unknown option */
    {
        if (short_too)
        {
            --optind;
            return (-1);
        }
        if (PRINT_ERROR)
            warnx(illoptstring, current_argv);
        optopt = 0;
        return (BADCH);
    }
    if (idx)
        *idx = match;
    if (long_options[match].flag)
    {
        *long_options[match].flag = long_options[match].val;
        return (0);
    }
    else
        return (long_options[match].val);
#undef IDENTICAL_INTERPRETATION
}

/*
    getopt_internal --
    Parse argc/argv argument vector.  Called by user level routines.
*/
static int getopt_internal(int nargc, char* const* nargv, const char* options,const struct option* long_options, int* idx, int flags)
{
    char* oli; /* option letter list index */
    int optchar, short_too;
    static int posixly_correct = -1;
    if (options == NULL)
        return (-1);
    /*
        XXX Some GNU programs (like cvs) set optind to 0 instead of
        XXX using optreset.  Work around this braindamage.
    */
    if (optind == 0)
        optind = optreset = 1;
    /*
        Disable GNU extensions if POSIXLY_CORRECT is set or options
        string begins with a '+'.

        CV, 2009-12-14: Check POSIXLY_CORRECT anew if optind == 0 or
                       optreset != 0 for GNU compatibility.
    */
    if (posixly_correct == -1 || optreset != 0)
        posixly_correct = (getenv("POSIXLY_CORRECT") != NULL);
    if (*options == '-')
        flags |= FLAG_ALLARGS;
    else if (posixly_correct || *options == '+')
        flags &= ~FLAG_PERMUTE;
    if (*options == '+' || *options == '-')
        options++;
    optarg = NULL;
    if (optreset)
        nonopt_start = nonopt_end = -1;
start:
    if (optreset || !*place)   /* update scanning pointer */
    {
        optreset = 0;
        if (optind >= nargc)   /* end of argument vector */
        {
            place = EMSG;
            if (nonopt_end != -1)
            {
                /* do permutation, if we have to */
                permute_args(nonopt_start, nonopt_end,
                             optind, nargv);
                optind -= nonopt_end - nonopt_start;
            }
            else if (nonopt_start != -1)
            {
                /*
                           If we skipped non-options, set optind
                           to the first of them.
                */
                optind = nonopt_start;
            }
            nonopt_start = nonopt_end = -1;
            return (-1);
        }
        if (*(place = nargv[optind]) != '-' || (place[1] == '\0' && strchr(options, '-') == NULL))
        {
            place = EMSG; /* found non-option */
            if (flags & FLAG_ALLARGS)
            {
                /*
                           GNU extension:
                           return non-option as argument to option 1
                */
                optarg = nargv[optind++];
                return (INORDER);
            }
            if (!(flags & FLAG_PERMUTE))
            {
                /*
                           If no permutation wanted, stop parsing
                           at first non-option.
                */
                return (-1);
            }
            /* do permutation */
            if (nonopt_start == -1)
                nonopt_start = optind;
            else if (nonopt_end != -1)
            {
                permute_args(nonopt_start, nonopt_end,
                             optind, nargv);
                nonopt_start = optind - (nonopt_end - nonopt_start);
                nonopt_end = -1;
            }
            optind++;
            /* process next argument */
            goto start;
        }
        if (nonopt_start != -1 && nonopt_end == -1)
            nonopt_end = optind;
        /*
               If we have "-" do nothing, if "--" we are done.
        */
        if (place[1] != '\0' && *++place == '-' && place[1] == '\0')
        {
            optind++;
            place = EMSG;
            /*
                 We found an option (--), so if we skipped
                 non-options, we have to permute.
            */
            if (nonopt_end != -1)
            {
                permute_args(nonopt_start, nonopt_end,
                             optind, nargv);
                optind -= nonopt_end - nonopt_start;
            }
            nonopt_start = nonopt_end = -1;
            return (-1);
        }
    }
    /*
        Check long options if:
        1) we were passed some
        2) the arg is not just "-"
        3) either the arg starts with -- we are getopt_long_only()
    */
    if (long_options != NULL && place != nargv[optind] && (*place == '-' || (flags & FLAG_LONGONLY)))
    {
        short_too = 0;
        if (*place == '-')
            place++; /* --foo long option */
        else if (*place != ':' && strchr(options, *place) != NULL)
            short_too = 1; /* could be short option too */
        optchar = parse_long_options(nargv, options, long_options,
                                     idx, short_too);
        if (optchar != -1)
        {
            place = EMSG;
            return (optchar);
        }
    }
    if ((optchar = (int) * place++) == (int)':' || (optchar == (int)'-' && *place != '\0') || (oli = (char*)strchr(options, optchar)) == NULL)
    {
        /*
               If the user specified "-" and  '-' isn't listed in
               options, return -1 (non-option) as per POSIX.
               Otherwise, it is an unknown option character (or ':').
        */
        if (optchar == (int)'-' && *place == '\0')
            return (-1);
        if (!*place)
            ++optind;
        if (PRINT_ERROR)
            warnx(illoptchar, optchar);
        optopt = optchar;
        return (BADCH);
    }
    if (long_options != NULL && optchar == 'W' && oli[1] == ';')
    {
        /* -W long-option */
        if (*place) /* no space */
            /* NOTHING */;
        else if (++optind >= nargc)   /* no arg */
        {
            place = EMSG;
            if (PRINT_ERROR)
                warnx(recargchar, optchar);
            optopt = optchar;
            return (BADARG);
        }
        else   /* white space */
            place = nargv[optind];
        optchar = parse_long_options(nargv, options, long_options,
                                     idx, 0);
        place = EMSG;
        return (optchar);
    }
    if (*++oli != ':')   /* doesn't take argument */
    {
        if (!*place)
            ++optind;
    }
    else     /* takes (optional) argument */
    {
        optarg = NULL;
        if (*place) /* no white space */
            optarg = place;
        else if (oli[1] != ':')   /* arg not optional */
        {
            if (++optind >= nargc)   /* no arg */
            {
                place = EMSG;
                if (PRINT_ERROR)
                    warnx(recargchar, optchar);
                optopt = optchar;
                return (BADARG);
            }
            else
                optarg = nargv[optind];
        }
        place = EMSG;
        ++optind;
    }
    /* dump back option letter */
    return (optchar);
}

/*
    getopt_long --
    Parse argc/argv argument vector.
*/
int getopt_long(int nargc, char* const* nargv, const char* options,const struct option* long_options, int* idx)
{
    return (getopt_internal(nargc, nargv, options, long_options, idx,
                            FLAG_PERMUTE));
}

/*
    getopt_long_only --
    Parse argc/argv argument vector.
*/
int getopt_long_only(int nargc, char* const* nargv, const char* options,const struct option* long_options, int* idx)
{
    return (getopt_internal(nargc, nargv, options, long_options, idx,
                            FLAG_PERMUTE | FLAG_LONGONLY));
}

//extern int getopt_long(int nargc, char * const *nargv, const char *options,
//    const struct option *long_options, int *idx);
//extern int getopt_long_only(int nargc, char * const *nargv, const char *options,
//    const struct option *long_options, int *idx);
/*
    Previous MinGW implementation had...
*/

#ifdef __cplusplus
}
#endif
#endif
